text: extern char src_start[];
  extern char src_end[];
  extern char dst_start[];
  
  void *memcpy(void *dest, void *src, unsigned n)
  {
    return (void *)0;
  }
  
  int main()
  {
    memcpy(dst_start, src_start, (unsigned)src_end - (unsigned)src_start);
    return 0;
  }
  